More python 2 support cleanup

setup.py

@@ -1,8 +1,6 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
 
-from __future__ import with_statement
-import sys
 from setuptools import setup
 from ydiff import PKG_INFO
 

tests/test_ydiff.py

@@ -16,16 +16,14 @@
 class DecodeTest(unittest.TestCase):
 
     def test_normal(self):
-        utext = 'hello'.encode('utf-8')
-        self.assertEqual('hello', ydiff.decode(utext))
+        octets = b'\xe4\xbd\xa0\xe5\xa5\xbd'
+        want = '你好'
+        self.assertEqual(ydiff.decode(octets), want)
 
     def test_latin_1(self):
-        text = '\x80\x02q\x01(U'
-        if sys.version_info[0] == 2:
-            decoded_text = text.decode('latin-1')
-        else:
-            decoded_text = text
-        self.assertEqual(decoded_text, ydiff.decode(text))
+        octets = b'\x80\x02q\x01(U'
+        want = '\x80\x02q\x01(U'
+        self.assertEqual(ydiff.decode(octets), want)
 
 
 class HunkTest(unittest.TestCase):
@@ -456,7 +454,7 @@ def test_is_new_neg(self):
 class DiffParserTest(unittest.TestCase):
 
     def test_parse_invalid_hunk_meta(self):
-        patch = """\
+        patch = b"""\
 spam
 --- a
 +++ b
@@ -469,7 +467,7 @@ def test_parse_invalid_hunk_meta(self):
         self.assertRaises(RuntimeError, list, parser.parse())
 
     def test_parse_dangling_header(self):
-        patch = """\
+        patch = b"""\
 --- a
 +++ b
 @@ -1,2 +1,2 @@
@@ -491,7 +489,7 @@ def test_parse_dangling_header(self):
         self.assertEqual(len(out[1]._hunks), 0)
 
     def test_parse_missing_new_path(self):
-        patch = """\
+        patch = b"""\
 --- a
 +++ b
 @@ -1,2 +1,2 @@
@@ -506,7 +504,7 @@ def test_parse_missing_new_path(self):
         self.assertRaises(AssertionError, list, parser.parse())
 
     def test_parse_missing_hunk_meta(self):
-        patch = """\
+        patch = b"""\
 --- a
 +++ b
 @@ -1,2 +1,2 @@
@@ -528,7 +526,7 @@ def test_parse_missing_hunk_meta(self):
         self.assertEqual(len(out[1]._hunks), 0)
 
     def test_parse_missing_hunk_list(self):
-        patch = """\
+        patch = b"""\
 --- a
 +++ b
 @@ -1,2 +1,2 @@
@@ -545,7 +543,7 @@ def test_parse_missing_hunk_list(self):
         self.assertRaises(AssertionError, list, parser.parse())
 
     def test_parse_only_in_dir(self):
-        patch = """\
+        patch = b"""\
 --- a
 +++ b
 @@ -1,2 +1,2 @@
@@ -572,7 +570,7 @@ def test_parse_only_in_dir(self):
         self.assertEqual(len(out[2]._hunks[0]._hunk_list), 3)
 
     def test_parse_only_in_dir_at_last(self):
-        patch = """\
+        patch = b"""\
 --- a
 +++ b
 @@ -1,2 +1,2 @@
@@ -591,7 +589,7 @@ def test_parse_only_in_dir_at_last(self):
         self.assertEqual(out[1]._headers, ['Only in foo: foo\n'])
 
     def test_parse_binary_differ_diff_ru(self):
-        patch = """\
+        patch = b"""\
 --- a
 +++ b
 @@ -1,2 +1,2 @@
@@ -621,7 +619,7 @@ def test_parse_binary_differ_diff_ru(self):
         self.assertEqual(len(out[2]._hunks[0]._hunk_list), 3)
 
     def test_parse_binary_differ_git(self):
-        patch = """\
+        patch = b"""\
 diff --git a/foo b/foo
 index 529d8a3..ad71911 100755
 --- a/foo
@@ -657,7 +655,7 @@ def test_parse_binary_differ_git(self):
         self.assertEqual(len(out[2]._hunks[0]._hunk_list), 3)
 
     def test_parse_svn_prop(self):
-        patch = """\
+        patch = b"""\
 --- a
 +++ b
 Added: svn:executable

ydiff.py

@@ -279,15 +279,15 @@ def is_binary_differ(self, line):
 class DiffParser(object):
 
     def __init__(self, stream):
-        self._stream = stream
+        self._stream = stream  # bytes
 
     def parse(self):
         """parse all diff lines, construct a list of UnifiedDiff objects"""
         diff = UnifiedDiff([], None, None, [])
         headers = []
 
-        for line in self._stream:
-            line = decode(line)
+        for octets in self._stream:
+            line = decode(octets)
 
             if diff.is_old_path(line):
                 # This is a new diff when current hunk is not yet genreated or
@@ -588,7 +588,7 @@ def _markup_mix(self, line, base_color):
 
 
 def markup_to_pager(stream, opts):
-    """Pipe unified diff stream to pager (less)."""
+    """Pipe unified diff stream (in bytes) to pager (less)."""
     pager_cmd = [opts.pager]
     pager_opts = opts.pager_options.split(' ') if opts.pager_options else []
 
@@ -623,14 +623,11 @@ def check_command_status(arguments):
         return False
 
 
-def decode(line):
-    """Decode UTF-8 if necessary."""
-    if isinstance(line, str):
-        return line
-
+def decode(octets):
+    """Decode bytes (read from file)."""
     for encoding in ['utf-8', 'latin1']:
         try:
-            return line.decode(encoding)
+            return octets.decode(encoding)
         except UnicodeDecodeError:
             pass